1. Field of the Invention
The present invention relates to an arthroscopic instrument for reconstruction of the anterior cruciate ligament (ACL) and to a method of ACL reconstruction using the instrument.
2. Description of the Related Art:
When a ligament or tendon becomes detached from the bone, surgery is usually required to re-secure the ligament or tendon. Often, a substitute ligament or graft is attached to the bone to facilitate re-growth and permanent attachment. Various methods of graft attachment are known, such as staples, suture over buttons, and interference screw fixation.
Staples and suture buttons are disadvantageous because they often do not provide a sufficiently strong attachment to withstand the normal tensile loads to which they are subjected. For example, with suture button fixation, the strand of suture coupling the button and the substitute ligament is the "weakest link in the chain" and if the suture breaks, the ligament will detach.
A stronger graft attachment is obtained by interference screw fixation, in which an interference screw is used to wedge a graft bone block to the wall of a graft tunnel. See, e.g., U.S. Pat. No. 5,211,647, herein incorporated by reference. Although interference screw attachment is more secure than using staples or suture buttons, it is sometimes not possible or desirable to provide such fixation, particularly in the femoral tunnel. For example, in situations where a previous reconstruction has been performed, a new femoral tunnel placed close to the previous tunnel may not allow for interference screw fixation. In other cases, a semitendinosus graft must be used since the previous reconstruction used the mid third patellar tendon. Although a bone-semitendinosus graft-bone construct may be prepared using a workstation as disclosed in allowed U.S. Ser. No. 08/186,604, now U.S. Pat. No. 5,397,357, such a procedure is time consuming, and often undesirable.
Accordingly, a need exists for a fixation technique which provides strong attachment of a semitendinosus graft in the femoral tunnel, without interference screw fixation.